The problem is, it does refresh on resize, but does not remember what
you drew on it.
Thus, you should use a memory-canvas% like I used:
; draws the log into the dc, eliminating error causing items.
(define (log->dc log dc)
(define (iter l)
(cond
[(empty? l)
empty]
[(with-handlers ([exn? (lambda args #t)])
(eval (append `(send ,dc)
(car l)))
#f) ; in case of error
(iter (cdr l))]
[else
(cons (car l) (iter (cdr l)))]))
(iter log))
(define-macro define-dc-proc
(lambda (name)
`(begin
(define (,name . args)
(set! log (cons (cons ',name args) log))
(refresh))
(public ,name))))
(define memory-canvas%
(class canvas%
(super-instantiate ())
(inherit get-dc)
(inherit refresh)
(define log empty)
(define-dc-proc draw-line)
(define-dc-proc draw-ellipse)
...
(define-dc-proc set-pen)
(define-dc-proc set-brush)
...
(define/override (on-paint)
(set! log (log->dc log (get-dc))))))
That should be about it, hope there are no errors.
This remembers what you drew on it with a log, then draws it again on-paint.
Katsmall the Wise
Vincent Hourdin wrote:
> For list-related administrative tasks:
>http://list.cs.brown.edu/mailman/listinfo/plt-scheme>>Hi,
>I am currently working on an interface which has to support an editor (1/3 of
>window size), a draw or a picture on which texts must be displayed,
>radio-boxes and things like that.
>I tried to build a canvas and started to draw in his dc%, but I've seen I
>cannot put my radio-box objects in this kind of display.
>So questions are:
>- How can I have a single window with control objects, several text displays
>and a draw or a picture of my draw ?
>- How can I maximize a window under linux ?
>- Why does (send my-frame refresh) has no effect ? How can I make it refresh
>itself automatically when it is moved or resized ... ?
>- How can I make my editor only take 1/3 of the frame space ?
>>Thank you !
>>>